Nicole C. Krämer

Bio: Nicole C. Krämer is an academic researcher from University of Duisburg-Essen. The author has contributed to research in topics: Psychology & Partial least squares regression. The author has an hindex of 50, co-authored 294 publications receiving 9703 citations. Previous affiliations of Nicole C. Krämer include Technical University of Berlin & University of Cologne.

Overview and recent advances in partial least squares

Abstract: Partial Least Squares (PLS) is a wide class of methods for modeling relations between sets of observed variables by means of latent variables. It comprises of regression and classification tasks as well as dimension reduction techniques and modeling tools. The underlying assumption of all PLS methods is that the observed data is generated by a system or process which is driven by a small number of latent (not directly observed or measured) variables. Projections of the observed data to its latent structure by means of PLS was developed by Herman Wold and coworkers [48,49,52].

Impression Management 2.0. The Relationship of Self-Esteem, Extraversion, Self-Efficacy, and Self-Presentation Within Social Networking Sites.

Abstract: Investigated the relationship between self-reported (offline) personality traits and (online) self-presentation in social networking profiles on the Internet. Social networking sites like MySpace, Facebook, and StudiVZ are popular means of communicating personality. Recent theoretical and empirical considerations of homepages and Web 2.0 platforms show that impression management is a major motive for actively participating in social networking sites. 58 users (mean age 22.98 years) of the German Web 2.0 site, StudiVZ.net, completed online questionnaires assessing extraversion (NEO Personality Inventory, NEO-FFI), self-esteem (Rosenberg Self-Esteem Scale, RSES), and efficacy of self-presentation, and their profiles were subject to a content analysis. Findings reveal a slight influence of extraversion on self-presentation, whereas there was no significant effect for self-esteem. Moveover, analyses of respondents' profiles showed that self-efficacy with regard to impression management is strongly related to the number of virtual friends, the level of profile detail, and the style of the personal photo.

Robustly estimating the flow direction of information in complex physical systems.

Abstract: We propose a new measure (phase-slope index) to estimate the direction of information flux in multivariate time series. This measure (a) is insensitive to mixtures of independent sources, (b) gives meaningful results even if the phase spectrum is not linear, and (c) properly weights contributions from different frequencies. These properties are shown in extended simulations and contrasted to Granger causality which yields highly significant false detections for mixtures of independent sources. An application to electroencephalography data (eyes-closed condition) reveals a clear front-to-back information flow.

Avatar-Mediated Networking: Increasing Social Presence and Interpersonal Trust in Net-Based Collaborations

Abstract: This study analyzes the influence of avatars on social presence, interpersonal trust, perceived communication quality, nonverbal behavior, and visual attention in Net-based collaborations using a comparative approach. A real-time communication window including a special avatar interface was integrated into a shared collaborative workspace. Communication modes under investigation were text chat, audio, audio-video, and avatar. Significant differences were found between text chat and all other communication modalities in perceived intimateness, co-presence, and emotionally-based trust. Microanalyses of nonverbal activity and visual attention point to similarities between video and avatar modes, both showing higher levels of exposure to the virtual other and visual attention, in particular in the initial phase of interaction as compared to text and audio.

A conversational agent as museum guide: design and evaluation of a real-world application

Abstract: This paper describes an application of the conversational agent Max in a real-world setting. The agent is employed as guide in a public computer museum, where he engages with visitors in natural face-to-face communication, provides them with information about the museum or the exhibition, and conducts natural small talk conversations. The design of the system is described with a focus on how the conversational behavior is achieved. Logfiles from interactions between Max and museum visitors were analyzed for the kinds of dialogue people are willing to have with Max. Results indicate that Max engages people in interactions where they are likely to use human-like communication strategies, suggesting the attribution of sociality to the agent.

疟原虫var基因转换速率变化导致抗原变异[英]／Paul H, Robert P, Christodoulou Z, et al//Proc Natl Acad Sci U S A

Abstract: 抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

Simultaneous inference in general parametric models.

Abstract: Simultaneous inference is a common problem in many areas of application. If multiple null hypotheses are tested simultaneously, the probability of rejecting erroneously at least one of them increases beyond the pre-specified significance level. Simultaneous inference procedures have to be used which adjust for multiplicity and thus control the overall type I error rate. In this paper we describe simultaneous inference procedures in general parametric models, where the experimental questions are specified through a linear combination of elemental model parameters. The framework described here is quite general and extends the canonical theory of multiple comparison procedures in ANOVA models to linear regression problems, generalized linear models, linear mixed effects models, the Cox model, robust linear models, etc. Several examples using a variety of different statistical models illustrate the breadth

Human biochemical genetics

Abstract: So far in this course we have dealt entirely with the evolution of characters that are controlled by simple Mendelian inheritance at a single locus. There are notes on the course website about gametic disequilibrium and how allele frequencies change at two loci simultaneously, but we didn’t discuss them. In every example we’ve considered we’ve imagined that we could understand something about evolution by examining the evolution of a single gene. That’s the domain of classical population genetics. For the next few weeks we’re going to be exploring a field that’s actually older than classical population genetics, although the approach we’ll be taking to it involves the use of population genetic machinery. If you know a little about the history of evolutionary biology, you may know that after the rediscovery of Mendel’s work in 1900 there was a heated debate between the “biometricians” (e.g., Galton and Pearson) and the “Mendelians” (e.g., de Vries, Correns, Bateson, and Morgan). Biometricians asserted that the really important variation in evolution didn’t follow Mendelian rules. Height, weight, skin color, and similar traits seemed to